Battleships were the name of the game back then. The Atlantic Fleet of the US Navy in 1913 had more battleships in it than the Germans brought to Jutland in 1916.
There were two other USN fleets afloat at the same time. Many of the battleships in the US line were pre-Dreadnoughts which would prove to be of dubious use in the coming war, but the US Navy was already large enough to match any potential enemy (except the British) on any ocean.
The US Navy also had the rare luxury of actual combat experience, having trounced the Spanish fleets in 1898. That meant that in 1913 the upper leadership of the US Navy was fairly well prepared to expand and reorganize to meet the demands of the war when they finally entered it in 1917, with many ship captains having started their careers with the battles of Manilla Bay and Santiago.
We attached one battleship division (comprised of our oldest, slowest, coal-burning battleships because the British were short of fuel oil) to the British Grand Fleet in 1917, which effectively ended any chances of the Germans challenging allied naval supremacy for the remainder of the war. Aside from a few feints, they never even tried after that.
So four or five battleships of the US Navy of 1913 were powerful enough to give the allies of World War I total supremacy in naval surface warfare. Behind it were three US fleets that were never needed. Most of those ships never fired a shot in anger.
One of them, the USS Utah, saw more action after it was converted to a target ship and then mistaken for an aircraft carrier by the Japanese at Pearl Harbor in 1941.
(Edit: I should add that one USN task force of today built around a single aircraft carrier, properly supplied, could destroy every major warship afloat in 1913, likely without sustaining damage or even casualties. So there's that, too.)
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